Cognitive Neuroscience

Cognitive Neuroscience Overview

A summary of key concepts related to neural anatomy, communication, and early neuroscience developments.

Neural Anatomy

• Key Components of Neuron:

  • Axon Hillock: Summation of stimuli leading to action potentials.

  • Terminal Button: Release of neurotransmitters into synapse.

  • Dendrite: Receives signals from other neurons.

  • Nucleus: Contains genetic material, regulates cellular activities.

  • Axon: Transmits action potentials away from the cell body.

  • Myelin Sheath: Insulates axons, speeding up signal transmission.

  • Cell Body/Soma: Contains the nucleus and organelles of the neuron.

  • Node of Ranvier: Gaps in the myelin sheath for saltatory conduction.

  • Synapse: Junction between neurons where communication occurs.

Neural Communication

• Propagation of Signals:

  • Action Potentials: Rapid depolarization of neuron membrane leading to nerve impulses.

  • Neurotransmitters: Chemicals transmitting signals across synapse.

  • Excitatory Postsynaptic Potential (EPSP): Increases likelihood of action potential.

  • Inhibitory Postsynaptic Potential (IPSP): Decreases likelihood of action potential.

  • Long Term Potentiation (LTP): Persistent strengthening of synapses due to repeated stimulation (Hebbian Learning).

Historical Perspectives in Neuroscience

• Ancient Greek & Roman Ideas:

  • Brain as a cooling mechanism for heart; 'sensus communis' concept.

• Middle Ages:

  • Ideas of three ventricles in brain (Imagination, Memory, Reason).

  • Ibn Sina's analogy for brain function regarding senses.

• Early Renaissance:

  • Emphasis on dissections and anatomical studies (Leonardo Da Vinci, Galen).

• Late Renaissance:

  • Framework for brain terminology (Cerebellum, Cerebrum).

  • Thomas Willis' studies laid foundations for cerebral circulation knowledge.

Localization of Function vs. Mass Action

• Case Studies:

  • Phineas Gage as an example of brain damage impacting personality

  • Broca’s area: left hemisphere correlates with language production (motor aphasia).

  • Wernicke’s area: comprehension deficits associated with fluent but nonsensical speech.

Memory Processing

• Brain Structures Supporting Memory:

  • Hippocampus: Critical for consolidation of new memories.

  • Amygdala: Emotion-associated processing and memory.

• Types of Memory:

  • Episodic Memory: Personal recollections of events.

  • Semantic Memory: Facts and concepts, independent of context.

  • Skill Memory: Memory of skills that may remain intact in amnesiacs (e.g., Clive Wearing’s piano playing).

End of Section Summary**

• Understanding innermost workings of the brain can provide insights into behaviors and cognitive functions.

  • Emphasis on the structure-function relationship essential for cognitive neuroscience.